exo-open with --launch option may not pass additional parameters to the applications. For an example to reproduce the issue, try to execute the command exo-open --launch TerminalEmulator --geometry=125x42 or modify Terminal Emulator launcher on the Xfce panel.
Duplicate, assigning to 9427 since it also has a downstream bug attached. *** This bug has been marked as a duplicate of bug 9427 ***